Major Hurricane Matthew Sets It Sights On Florida

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Hurricane Matthew
5:00 PM EDT on October 05, 2016
Location 22.5 N -75.7 W
Winds: 120 mph Gust: 150 mph
Pressure: 963 mb
Category: 3
Moving: NW at 12 mph

Major Hurricane Matthew is moving its way through the Bahamas now as a strong category 3 hurricane. The eye has diminished as convection around the eye blows up. The satellite animation of this convection and how hard this convection has hit the tropopause resulting in major outflow along the northeast side of the core of the storm is amazing. You can see the outflow in the satellite image above (wispy clouds fanning out just northeast of the center). It really shows the power that one of the hurricanes can have.

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Rain has begun to show up on the Miami, FL radar associated with an outer band from Matthew. The showers and thunderstorms over central and western Florida are not associated with Matthew. Over the next couple of hours Florida will begin getting rain bands that are associated with Matthew. Once this begins, conditions over south Florida will begin to deteriorate as the core of the hurricane approaches the coast.

Matthew is forecast to maintain its current strength though the environment in the area remains conducive for strengthening. It will be moving relatively slowly so it has time to tap into this potential energy before it makes its way to the coast. Whether or not Matthew can regain a more organized core is what the limiting factor is. The eye today has been somewhat disrupted and very spread out. This could be the reason it has had difficulty strengthening to its max potential. That could change if the previously mentioned convection wraps completely around the eye over the next couple of hours. The most recent IR satellite images are beginning to suggest that this is what could be taking place now. If this convection does wrap around, we would see the eye tighten up a bit and wind speeds increasing.

It doesn’t appear wind sheer will be much of an issue for Matthew until it gets closer to the coast. This will be one feature that would help to weaken the storm over time. As it approaches land there really isn’t much that will stand in its way to being a strong category 3 or 4 storm. Matthew could interact with the dry air over land but the storm has to be closer to land and it would take some time before the dry air is ingested into the storm. I do believe that once this reaches the coast (whether it makes landfall or not) and begins to travel north, the dry air will become an issue for the storm. That combined with the increased sheer will help weaken the storm as it heads northward.

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Water vapor satellite image showing dry air over land (oranges).

The models continue to push Matthew westward and potentially on land on the east coast of Florida. Right now and movement to the left or right of the forecast track could impact where landfall could be or if no landfall occurring at all. It is very important to note that it doesn’t matter if the center makes landfall or doesn’t since hurricane force winds extend out from the center of the storm and tropical storm force winds even further. Every one on the Florida Peninsula could experience at least tropical storm conditions over the next 48 hours.

The current forecast track is also probably the worst case scenario. With typical land falling hurricanes a limited area of the coast and inland sections are impacted. This hurricane will pass through several heavily populated areas as it moves right along the coast. This means millions of people will be impacted by this storm. If you live between Miami and Cape Hatteras, this hurricane could impact you over the next 72 hours.

What happens after it hits Florida through South Carolina is still a very uncertain. The 12Z and 18Z GFS runs have trending with a weaker trough over the northern US but have picked up some between the 12Z and 18Z runs. This faster pace will allow a more northerly track but only by maybe 100 miles. The 12Z Euro had a stronger trough and a quicker storm (which I personally feel the Euro has a better handle on the trough though I still think the trough will be a little stronger as I have mentioned in my previous discussion) leading to a track similar to a few days ago with the center of the storm just off the NC coast and pulls away at Cape Hatteras.

Why do these features matter so much?

As the storm rounds the ridge of high pressure over the Atlantic, there is going to be a large trough over the Great Lakes region. The models have been showing a weaker trough over time which creates a more zonal flow or a west-east flow. What this allows it to do is develop a ridge to quickly move in and from the northwest and push Matthew more due east once it reaches the South Carolina coast.

Ridge over the Great Lakes region and placement of Hurricane Matthew.
Ridge over the Great Lakes region and placement of Hurricane Matthew.

 

Ridge quickly builds in behind the weaker departing trough. This shifts Matthew due east.
Ridge quickly builds in behind the weaker departing trough. This shifts Matthew due east.
Surface level shows high pressure over the north Atlantic and high pressure building in from Canada behind the weak departing trough.
Surface level shows high pressure over the north Atlantic and high pressure building in from Canada behind the weak departing trough.

This slows the storm down and allows the ridge to build right into the northeastern US which then turns Matthew to the southwest. This also creates a new level of difficulty because you will have Tropical Storm Nicole or whats left of it sitting south of Bermuda. How Matthew or whats left of Matthew interacts with Nicole is very unpredictable. It is at this time frame where the long range models diverge greatly. But that is beyond the current forecast time frame I will concentrate on tonight.

I was using the 18Z GFS model above as an example of one of the possible forecasts at this time. I also want to explain why the Euro is different somewhat than the GFS.

In the 12Z Euro you have a similar starting position as the GFS. The Euro out 72 hours shows a faster storm as well as a slightly stronger trough over the Great Lakes. Both have the storm ride around the ridge over the Atlantic but once it reaches the South Carolina coast the tracks vary slightly. The slightly stronger trough and faster storm will have a track closer to the North Carolina coast. It will not alter the forecast track to the south except for timing. This primarily impacts the track from South Carolina up near the North Carolina coast. This slight spread between the two models is important for impacts along the North Carolina coast. The GFS turns the storm out earlier with the storm further off the North Carolina coast while the Euro turns the storm a little later which brings it closer to the North Carolina coast. I will also point out that the CMC, NAM, HWRF, and GFDL all lean towards the Euro solution over the GFS solution.

I can’t say with any certainty which of these models will prevail. The NHC released its official forecast on Major Hurricane Matthew.

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The actual spaghetti plot for forecast models are tightly grouped near the east coast of Florida representing high confidence in the forecast track of the storm. The models become more spread out off the South Carolina coast representing a less confident forecast track.

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This hurricane will affect the southeast coast for the next couple of days. If you live in these areas, listen to NHC, NWS, or local authorities for official information regarding this dangerous situation. If you have time to prepare do so now. If you have a plan, make sure you are ready to take action. This will be a historic storm and is extremely dangerous, not just because of its strength but because it will cover such a large area and population.

I will write an update tomorrow morning, time permitting, and later in the afternoon.

I wish everyone along the southeast coast luck as we ride out this storm.

 

 

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